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INTRODUCTION

One of the major goals for early silicon is to boot a commercial operating system (OS), shortly after the arrival of first silicon. In order to increase the probability of success we decided to use an operating system kernel to validate the processor in addition to using conventional pre-silicon testing methods. Traditional microprocessor validation includes feature validation, unit testing, and random instruction testing. The potential shortfall of these methods is that they often don't exercise the processor in the same environment in which it is later expected to run. In other words, an operating system programmer often thinks of a different, but legal way, of exercising processor functionality that might not be covered by conventional methods of validation. Therefore, running an operating system kernel to exercise key OS-related features pre-silicon turned out to be a worthwhile effort. The following sections detail the issues we had to resolve during this effort.